Flint Hit With Bacterial Illness as Residents Shun City Water

Residents of Flint, Mich., affected by the contaminated-water crisis have added a new complication to their lives: an outbreak of shigellosis, a bacterial illness that is easily transmitted when people do not wash their hands.

Health department officials in Genesee County, where Flint is the largest city, said there has been an increase in the gastrointestinal illness, which can lead to severe diarrhea, fever, nausea, vomiting, cramps and stools containing blood and mucus, according to a statement issued last month.

A shower in the home of Tracey McCloud-Atkins in Flint, where residents still don’t trust the water.CreditBrittany Greeson for The New York Times

The number of cases of shigellosis ((pronounced she-guh-LO-sis) throughout the state has totaled 454 so far this year. There were 515 cases of the food-borne illness in all of 2015, and 309 cases in 2014.

“Shigella cases are on the rise across Michigan,” the county health department statement said.

Residents are also using baby wipes, which they get free at bottled-water-distribution centers, to clean their hands. But that may be contributing to the current transmission of the shigella bacteria, because they are not chlorinated and do not kill the bacteria.

A report published in August by the Michigan health department, the C.D.C. and other agencies about rashes in Flint showed that a large percentage of residents had changed their frequency or methods of bathing, using bottled water or water that did not come from the Flint municipal system. About 4 percent of 185 people surveyed said they used baby wipes.

Matt Karwowski, a medical epidemiologist with the C.D.C., said in a telephone interview on Tuesday that outbreaks of shigellosis were not uncommon in the United States, particularly during the summer months. He said there was concern that the outbreak in Genesee could be larger than the usual rate of infection.

“There is definitely some question about whether changes in hand-washing and hygiene practices may be playing a role,” he said. “People in Flint have been concerned about the safety of their water supply, and that may be playing a role in their hygiene practices.”

Mr. Karwowski said that the illness sometimes can go away on its own, and that the current strain of shigella bacteria was not one of those that demonstrate a resistance to antibiotics. Infection with some strains of shigella can be fatal by producing a toxin that harms the kidneys, he said.

It’s not the first time that a disease outbreak has been linked to the Flint water system. It was also associated with an outbreak of Legionnaires’ disease from June 2014 to October 2015. At least 87 people developed the disease, and 10 died, health officials said in January.

The outbreak coincided with Flint’s change to the new water source, and officials said they could not rule out a connection.

A version of this article appears in print on , on Page A11 of the New York edition with the headline: Bacterial Illness on the Rise in Flint as Residents Shun City Water. Order Reprints | Today’s Paper | Subscribe